ARM: dts: sun5i-a10s-wobo-i5: Enable ldo4 too

It seems that the wifi chip is powered by both ldo3 and ldo4 tied
together and that using only one results in the wifi-chip dropping of
the USB bus sometimes.

Ideally we would have a proper way of modelling this (this is being
worked on), but currently we do not. This is not an issue since we need
to keep these regulators always-on anyways, due to these boards
crashing when ldo3/4 get turned back on after having been turned off.

Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Maxime Ripard <maxime.ripard@free-electrons.com>